My client, which is basically just one guy, uses this system at trade shows. He probably uses it at 5-15 trade shows per year. And at each show it is used by probably hundreds of vendors and thousands of attendees. I am not sure how he charges for it, I don't know if the trade show just pays him a lump sum to provide it to all the vendors or if each vendor pays separately.

Another point is that one of his friends, who also does the same thing, also used this system for maybe 20 trade shows. So at one point there were two instances of this system running. But when Covid hit this second instance got shut down because the guy had to take another job.

Also to clarify, I am the only software developer involved. I do all the planning, coding, maintenance, upgrades, troubleshooting of technical issues, etc.

So through all this I've been charging hourly and for the last 5 years I make about $1,000 to $2,000 per year. I am guessing that my client makes tens of thousands or maybe even hundreds of thousands on an annual basis when he uses this system at trade shows. So I'm sitting here thinking, I need to renegotiate my remuneration setup because I don't think I'm being payed enough.

5 months ago my client asked for a new feature and I said first I need to restructure how I'm paid I want to partner with you instead of hourly pay. He never responded until last week. Now I'm wondering how to respond back.

So what remuneration setup should I propose to him? Should I ask for 15% of revenue? Should I ask for $5k per show? What payment setup would you try and get if you built this system? Are there questions I should ask my client before asking for a different pay structure? For example, should I ask how much he's making per year?